//
// Created by WuShiHai on 23/11/2016.
//
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>

#define BUF_SIZE 100

void error_handling(char *message);

int main(void){

    int fd;
    char buf[BUF_SIZE];

    fd = open("data.txt",O_RDONLY);
    if (fd == -1){
        error_handling("open() error!");
    }
    printf("file descriptor: %d",fd);

    if (read(fd,buf, sizeof(buf)) == -1){
        error_handling("read() error!");
    }

    printf("file data: %s", buf);
    close(fd);

    return 0;
}

void  error_handling(char *message){
    fputs(message, stderr);
    fputc('\n',stderr);
    exit(1);
}